1. FIELD OF THE INVENTION
This application is directed to vinyl pyrrolidinone phosphorodithioates as multifunctional additives and lubricant compositions containing same.
2. DESCRIPTION OF RELATED ART
The use of phosphorodithioate compositions, especially the corresponding salts of phosphorodithioates, such as zinc dialkylphosphorodithioates (commonly known as zinc dithiophosphates) have found widespread commercial use for several decades in engine oils as multifunctional antiwear, peroxide decomposing, and bearing corrosion inhibiting additives.
1-Vinyl-2-pyrrolidinone (also known as N-Vinyl Pyrrolidone) is an essential monomeric building block for the preparation of many useful specialty polymers and copolymers. This heterocyclic compound imparts superb solubility, stability, and alkalinity, and therefore, can provide many potentially beneficial characteristics, such as anti-corrosion, anti-oxidation properties to lubricants when it is built into the additive structures.
It has now been found that the use of these phosphorodithioate-derived pyrrolidinones provides exceptional antioxidant and antiwear/EP activity with potential corrosion inhibiting, anti-fatigue and high temperature stabilizing properties.